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While it may be easy to denounce homeless people as second-class citizens, due to unstable mental health, a new study finds that less than half of all homeless men suffer from a traumatic brain injury (TBI), and among those that do, most injuries were sustained before the men lost their homes.

We place a great deal of importance on normalcy in the U.S. — in physical appearance, but also in mental well-being. Homelessness, for this reason, is seldom looked upon as a circumstance, but rather a pathology. We see homeless people not as individuals who need rehabilitation, but as furniture, a blemish on the social landscape. And because of poor mental health care in the U.S., help for these men and women rarely comes.

Prior research has also found that homeless people put a tremendous burden on the public health care system. A study conducted earlier this year found TBI is seven times more common among the homeless than the general population. They’re also more likely to visit the ER, putting a strain on a system that must eat the costs of uninsured patients who have little more than pennies to their name.

The latest study, conducted by researchers at St. Michael's Hospital in Toronto, found that out of 111 homeless men, ages 27 to 81, some 45 percent had suffered a traumatic brain injury during their lifetime. Out of that group, interestingly enough, 87 percent had suffered the TBI before losing their homes and 70 percent while they were still children. Men under 40 were most likely to have sustained an injury resulting from a drunken fall, while assault was most often the cause for men over 40.

What this suggested to researchers was an imbalance in the way people tend to view homelessness compared to the men’s actual circumstances. It may be the case that poor life choices led to a TBI (such is more likely in the men under 40, who suffered injuries after heavy drinking), but the fact so many men had sustained the TBI in childhood suggested otherwise. Dr. Jane Topolovec-Vranic, a clinical researcher in the hospital's Neuroscience Research Program, said watching out for these signs of injury could have lifelong effects, avoiding the slide into homelessness being just one among them.

The findings also poke holes in the argument that all homeless people are products of addiction. Research conducted by the National Coalition for Homelessness has already shown that addictions are both causes and effects of homelessness, with roughly 38 percent of people dependent on alcohol and 26 percent abusing other drugs. Indeed, drugs may precipitate certain injuries, but substance abuse also has a numbing effect. Ultimately, both issues must be addressed simultaneously.

At stake are homeless people’s mental and physical health. And if they are to have any chance at recovery, overcoming the bevy of obstacles that have come their way must be done from a unified front. “Screening for such injury may provide insight into the cognitive, behavioural and mental health issues that homeless persons face,” the research team wrote. “Additional research on temporal relationships and other factors related to traumatic brain injury and homelessness would be valuable.”